Electrosurgery involves applying relatively high voltage, radio frequency (RF) electrical current to cut tissue, to coagulate or stop blood flow from tissue, or both to cut and coagulate tissue simultaneously. The electrosurgical energy of the high voltage, RF electrical current is created by an electrosurgical generator. The electrosurgical energy is applied to the tissue with an accessory or instrument connected to the electrosurgical generator. Electrical characteristics of the applied electrosurgical energy determines whether cutting, coagulating or simultaneous cutting and coagulating occurs.
In monopolar electrosurgery, the accessory has a single active electrode from which the electrosurgical energy is applied to the tissue at a surgical site to achieve the cutting, coagulating or simultaneous cutting and coagulating effects. The electrical current flows from the single active electrode through the patient to a single, relatively large, return electrode connected to the patient at a location remote from the surgical site. The return electrode collects the current from the patient's body and returns it to the electrosurgical generator, thereby completing an electrical circuit through the patient.
The delivery of electrosurgical energy to the accessory is controlled by the surgeon depressing or closing a switch on a handpiece of a finger switched accessory or by stepping on a foot switch located on the floor to deliver energy to a foot switched accessory. The handpiece of a finger switched accessory typically includes two finger switches, one for delivering electrosurgical energy for cutting and the other for delivering electrosurgical energy for coagulation. When using a foot switched accessory, closing the foot switch delivers the type of electrosurgical energy which the surgeon has selected from the front panel controls of the electrosurgical generator.
A three-prong electrical connector is used to connect a finger-switched monopolar accessory to the electrosurgical generator. One of the prongs conducts the electrosurgical energy to the active electrode. A second prong conducts a cut activation signal to the electrosurgical generator to cause it to deliver the cutting electrosurgical energy. A third prong conducts a coagulation activation signal to the electrosurgical generator to cause it to deliver the coagulating electrosurgical energy. The front panel of the electrosurgical generator includes a receptacle by which to connect the three-prong electrical connector to the electrosurgical generator. Three ports of the receptacle each receive one each of the prongs of the three-prong connector. The size and spacing of the ports and the prongs is standardized, so that a common finger-switched monopolar accessory can be connected to and used with a common electrosurgical generator.
A single-prong electrical connector is typically used to connect a foot-switched monopolar accessory to the electrosurgical generator. The single prong conducts the electrosurgical energy to the monopolar instrument, in response to the closure of the foot switch. The single prong is considerably larger than any of the three prongs associated with a three-prong electrical connector. The typical type of single-prong electrical connector is a Bovie #12 connector, which is standardized in size and shape for use with an electrosurgical generator. The foot switch is separately connected to the electrosurgical generator with its own connector that is usually located on a back panel of the generator.
Because of the differences in size and configuration of the three-prong electrical connector for a finger-switched accessory compared to the single-prong electrical connector for a foot-switched accessory, separate receptacles for connecting both types of connector are provided on most electrosurgical generators. Providing at least one receptacle for each type of monopolar accessory consumes valuable space on the front panel of the electrosurgical generator. The front panel must present various switches, selectors and displays used to operate and control the electrosurgical generator. The size of the front panel is typically dictated by the usual and expected dimensions for the electrosurgical generator, which must fit onto a cart and into other standard support equipment typically used in a surgical operating room. More advanced electrosurgical generators usually provide multiple receptacles for both the three-prong and the single-prong electrical connectors on the front panel to accommodate the simultaneous use of multiple monopolar accessories. One surgeon may use one or more monopolar accessories on an alternating basis during a single surgical procedure, or multiple surgeons may perform procedures simultaneously at separate surgical sites on the same patient while using their own monopolar accessories. An electrosurgical generator should not have only one three-prong receptacle or only one single-prong receptacle because a surgeon may have a preference for either finger-switched or foot-switched accessories and the provision of only one type of receptacle would not universally accommodate all the preferences of all surgeons.
An electrosurgical generator which is presently in use has a single receptacle within which there are four ports. One of the ports receives the single-prong electrical connector of the foot-switched accessory, and the other three ports receive the three prongs of the electrical connector of the finger-switched accessory. All four ports are integrated into approximately the same amount of front panel space normally consumed by a receptacle for the three-prong electrical connector. This four-port integrated receptacle conserves front panel space by allowing the three-prong electrical connector of a finger-switched electrosurgical accessory or the single-prong electrical connector of a foot-switched accessory to be connected in the space normally consumed by only one receptacle. However, the four-port receptacle does not simplify or reduce the size of the internal electrical connections of the electrosurgical generator. One port of the four-port receptacle delivers electrosurgical energy to an energy-conducting prong of the three-prong electrical connector, and another port of the four-port receptacle delivers electrosurgical energy to an energy-conducting prong of the single-prong electrical connector. The other two ports connect with control prongs of the three-prong electrical connector electrically connect the two finger switches to the electrosurgical generator.
Each of the two separate energy-delivery ports in this previous integrated four-port receptacle has its own separate electrical contact and its own separate energy-delivery relay. Closing the energy-delivery relay conducts the electrosurgical energy to the energy-conducting prong. Each energy-delivery relay must be separately controlled, according to the type of electrical connector inserted into the receptacle. Using two separate energy-delivery relays and two separate electrical contact assemblies, one for each energy-delivery port, increases the number of components, the complexity of the components, the amount of wiring and control circuits and logic required to deliver the electrosurgical energy to the energy-delivery port appropriate for the type of electrical connector connected to the generator. In this situation, the number of components used and housed within the interior of the electrosurgical generator is the same as if two separate and non-integrated receptacles are provided. More components consume more interior space and discourage attempts to reduce the size of the electrosurgical generator. The size, complexity and cost of the electrosurgical generator is not materially decreased by the four-port receptacle.